Run the compiled Java class with the java command, passing any number you want to convert as a command-line argument.
For example:
java WordConverter 123456
You should see output like:
Input: 123456
Output: one hundred twenty three thousand four hundred fifty six
You can run the program with different numbers as arguments, including negative numbers like -456.
java WordConverter -456
This would output:
Input: -456
Output: negative four hundred fifty six